How do you clean tube pins?


I'm sure there must be some discussion on how to clean tube pins (both power and small input tubes), but I haven't been able to find much on the subject. Specifically:

1) As tube pins are so close to each other, what tool do you use to clean the pin?
2) What solvents do you use?
3) How often should you clean tube pins?
4) Any other advise / suggestions you'd like to share.

In advance, thanks for any suggestions you may offer.
louisl

Showing 1 response by atmasphere

You can clean sockets and tube pins but it should be done with caution!

Do not use any abrasives. The best thing I have found is spray contact cleaner that leaves no residue. DO NOT UNDER ANY CIRCUMSTANCES USE ANY "CONTACT ENHANCERS"!!!

-If you do, you can contaminate the socket and possibly ruin the circuit board on which the socket sits or at the very least the socket itself. Contact enhancers can be identified as they usually have to be applied with some sort of swab and they most definitely leave a fine film. This film can migrate across insulators such as the socket material. This can degrade the performance of the circuit dramatically over time, and can even damage components! We had a customer ruin a set of circuit boards in his MP-1 preamp once- the only solution was to replace both boards with new components.

Tubes can have high voltage differentials on them so if you contaminate the tube or its socket you can get leakage voltages and stray capacitances that should not be in the circuit; that is how damage and degradation can result.

So: to clean the pins or the socket, use a spray contact **cleaner** that leaves no residue. Spray the pins of the tube itself, wipe off excess, insert in the socket and pull it out again. If a miniature tube, rock the tube in the socket and you are done. No more than that!

Tin plating is a common sight on tubes and tube sockets. Like gold, tin is highly conductive and does not corrode easily. Unlike gold though, it is rather hard and so holds up much longer to use. However it is, just like gold, a plating on the pin of the tube and the socket. If the plating is damaged by abrasion (such as steel wool) the result is that the material beneath the plating will be exposed to oxygen and could see significant corrosion! SO DO NOT USE ABRASIVES WHEN CLEANING TUBE PINS OR SOCKETS!

BTW, the use of silver and gold in tube connections really isn’t that great an idea. Tin is much more reliable in the long term. This is why you can still find tubes and tube sockets on ebay that are decades old and yet are perfectly serviceable.